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Abstract:

A broadband dual-polarized omni-directional antenna and a feeding method
using the same are provided. By setting a vertically polarized antenna
and a horizontally polarized antenna each in co-axial, the horizontally
polarized antenna is attached to an upper surface and a lower surface of
the attaching plate respectively by two arms of a folded dipole and the
two arms connect to an inner conductor and an outer conductor of a feed
line so that the dual-polarized antenna may have a comparatively broad
bandwidth. At the same time, since the dual-polarized ceiling antenna has
a good isolation effect and coverage balance, it may work as the MIMO
antenna in the LTE and WLAN systems effectively and may be used in the 2G
and 3G networks to improve the data transmission rate.

Claims:

1. A broadband dual-polarized omni-directional antenna, wherein the
broadband dual-polarized omni-directional antenna comprises a vertically
polarized antenna (20) and a horizontally polarized antenna (30) each set
in co-axial; the horizontally polarized antenna (30) comprises an
attaching plate (32) and a folded dipole (31) attached to the attaching
plate (32) for receiving and transmitting electromagnetic waves; two arms
of the folded dipole (31) are attached to an upper surface and a lower
surface of the attaching plate (32) respectively, with one arm connecting
to an inner conductor of a first feed line and the other arm connecting
to an outer conductor the first feed line.

2. The broadband dual-polarized omni-directional antenna according to
claim 1, wherein the two arms of the folded dipole are connected through
a metallized through hole.

3. The broadband dual-polarized omni-directional antenna according to
claim 1, wherein the antenna further comprises a vertical polarized guide
sheet (50) and a connecting component (60); the connecting component (60)
connects the attaching plate (32) of the horizontally polarized antenna
(30) with the vertical polarized guide sheet (50) to have the vertical
polarized guide sheet (50) fixed between the horizontally polarized
antenna and the vertically polarized antenna.

4. The broadband dual-polarized omni-directional antenna according to
claim 1, wherein the vertically polarized antenna (20) comprises an
antenna component (22) in a form of spherical segment and an antenna
component (21) in a form of cone extending from a lower end of the
antenna component (22) in the form of spherical segment, and the antenna
component (21) in the form of cone is connected with a second feed line.

5. The broadband dual-polarized omni-directional antenna according to
claim 4, wherein a vertical distance between the lower surface of the
attaching plate (32) of the horizontally polarized antenna (30) and a top
end of the antenna component (22) in the form of spherical segment of the
vertically polarized antenna (20) ranges between 8 mm and 15 mm.

6. The broadband dual-polarized omni-directional antenna according to
claim 1, wherein the arms are in a polygon in a form of a segment of
circular ring or nearly circular ring and leads in the arms are led from
an inner edge of the arms and are connected to the inner conductor or the
outer conductor of the first feed line.

7. The broadband dual-polarized omni-directional antenna according to
claim 6, wherein the horizontally polarized antenna (30) comprises N
folded dipoles (31), where N is an even number and the N folded dipoles
(31) are arranged uniformly on the attaching plate (32) in an axial
symmetry.

8. The broadband dual-polarized omni-directional antenna according to
claim 7, wherein an outer edge of the arm of the folded dipole (31) is
adjacent to an outer edge of the attaching plate (32) and an inner edge
of the arm is adjacent to a center of the attaching plate (32).

9. The broadband dual-polarized omni-directional antenna according to
claim 8, wherein leads of each folded dipole (31) connecting to the inner
conductor of the first feed line are connected together and leads
connecting to the inner conductor of the first feed line are connected
together so that the N folded dipoles (31) are connected in parallel.

10. The broadband dual-polarized omni-directional antenna according to
claim 6, wherein a gap in a form of a segment of circular ring or a
segment of approximately circular ring exists in the arm.

11. The broadband dual-polarized omni-directional antenna according to
claim 1, wherein the vertical polarized antenna is applied in an indoor
GSM coverage system and an indoor CDMA coverage system; when the
broadband dual-polarized omni-directional antenna is applied in a WCDMA
system, a CDMA2000 system or a TD-SCDMA system, the vertically polarized
antenna and the horizontally polarized antenna together form a
dual-channel antenna; when the broadband dual-polarized omni-directional
antenna is applied in a TD-LTE system or a WLAN system, the broadband
dual-polarized omni-directional antenna is an MIMO antenna.

12. A feeding method using the broadband dual-polarized omni-directional
antenna according to claim 1, wherein the method comprises: using the
horizontally polarized antenna to receive and transmit horizontal
polarized waves; using the vertically polarized antenna to receive and
transmit vertical polarized waves.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and benefits of Chinese Patent
Application Serial No. 201010504764.6 filed with the State Intellectual
Property Office of P. R. China on Oct. 8, 2010 with a title of "BROADBAND
DUAL-POLARIZED OMNI-DIRECTIONAL ANTENNA AND FEEDING METHOD USING THE
SAME", the entire content of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a mobile communication field, and more
particularly to a broadband dual-polarized omni-directional antenna
(BDOA) and a feeding method using the same.

[0004] 2. Description of the Prior Art

[0005] In the Advanced International Mobile Telecommunication
(IMT-Advanced) system, both the Time Division Duplexing (TDD) and the
Frequency Division Duplexing (FDD) use the Multi-Input-Multi-Output
(MIMO) antenna technology.

[0006] According to the MIMO antenna technology, multiple transmitting
antennas and multiple receiving antennas are used at the transmitting
side and the receiving side respectively. The radio signal is transmitted
and received through the multiple antennas at the transmitting side and
the receiving side so as to improve the quality of service (such as bit
error rate or data speed) for each user. For the traditional
Single-Input-Single-Output (SISO) antenna system, MOMO antenna system may
improve the frequency spectrum utilizing rate and make it possible to
provide higher speed data services with limited radio frequency bands.

[0007] According to the practical requirement for the MIMO antenna system,
the MIMO antenna array may take the form of 2×2 or 4×4 and
the mono-polarized antenna or dual-polarized antenna may be used as the
array unit for the MIMO antenna system. The mono-polarized antenna refers
to the one with dipoles arranging into one column in the same direction
and receiving the radio signal from one direction. The mono-polarized
antenna may be vertically polarized, horizontally polarized or
±45° polarized with respect to the datum level. The
dual-polarized antenna refers to the one with dipoles arranging into two
columns in two directions and receiving the radio signals from two
directions. Two inner dipoles of the dual-polarized antenna may be
polarized differently. For example, one dipole may be horizontally
polarized (horizontally polarized antenna) and the other dipole may be
vertically polarized (vertically polarized antenna); or one dipole may be
±45° polarized (±45° antenna) and the other dipole
may be -45° polarized (-45° antenna).

[0008] According to the directionality of the antenna(s), there may be the
omni-directional antenna and the directional antenna. The
omni-directional antenna refers to the one without the maximum direction
when transmitting and receiving radio signal in the horizontal plane,
which has a comparatively low antenna gain and a comparatively short
transmission distance of the radio signal. Therefore, the
omni-directional antenna is mainly adapted to use in a point to
multi-point environment which does not have a strict requirement on
transmission distance, for example in the indoor environment. Compared
with the omni-directional antenna, the directional antenna has the
advantages of good directionality, concentration of energy in a specific
direction, high gain, comparatively long transmission distance,
comparatively strong anti-interference ability and is more adapted to use
in a long distance point-to-point communication. The disadvantages of the
directional antenna are small coverage, difficult in mounting and
adjusting, and requiring the antennas at the two transmission points to
be aligned so as to guarantee the transmission of the radio signal.

[0009] The current MIMO antenna system is mainly designed for outdoor
environment. For the indoor environment, the MIMO antenna system is
designed to generally include a plurality of mono-polarized
omni-directional antennas that are vertically polarized because of the
complexity of the environment and the requirement of a comparatively
broadband coverage.

[0010] In the current indoor MIMO antenna system that adopts the
mono-polarized omni-directional antenna as the array unit, since the
frequency utilization rate of the mono-polarized antenna is low, the data
transmission rate is comparatively low. In addition, in order to
guarantee the high capacity of the indoor MIMO antenna system, the number
of the mono-polarized antennas is required to be comparatively large,
which leads to a comparatively large occupation of space by the indoor
MIMO antenna system. Therefore, an omni-directional antenna that may
improve the frequency utilization rate and occupy a comparatively small
space is needed to work as the array unit of the indoor MIMO antenna
system.

[0011] Considering that the dual-polarized omni-directional antenna may
separate overlapped frequencies compared with the mono-polarized
omni-directional antenna and improve the frequency utilization rate, it
is proposed to use the dual-polarized omni-directional antenna as the
array unit for the indoor MIMO antenna system, which may improve the
frequency utilization rate while occupying a comparatively small space.
As shown in FIG. 1, which is a schematic diagram showing a structure of a
dual-polarized omni-directional antenna, the dual-polarized
omni-directional antenna has one vertically polarized antenna 1 and four
horizontally polarized antennas 2. The working frequency of the antenna
ranges from 225 MHz to 400 MHz. Therefore, compared with the
mono-polarized omni-directional antenna, although the dual-polarized
omni-directional antenna may improve the frequency utilization rate and
the MIMO antenna system constituted by the dual-polarized
omni-directional antenna occupies a reduced space, the dual-polarized
omni-directional antenna can hardly be used in the mobile communication
system because of the dual-polarized omni-directional antenna working at
a comparatively low frequency and a comparative ovality of the horizontal
polarization.

[0012] Besides the above problems of the MIMO antenna, in the 3rd
generation (3G, i.e. TD-SCDMA, WCDMA and CDMA2000) mobile communication
system, the indoor antenna still uses the mono-polarized antenna as the
2nd generation (2G) mobile communication system. However, since the
3G system has a comparatively high frequency, the coverage distance of
the mono-polarized antenna using the single channel mode is greatly
reduced and the number of the antennas has to be multiplied to compensate
for the reduction of the coverage distance. The dual-polarized
omni-directional (ceiling) antenna using the dual channel mode may meet
the coverage requirement of the network with the same number of antennas
as that of the 2G network by utilizing the polarization gain effect of
the polarization diversity. However, the current dual-polarized
omni-directional (ceiling) antenna still works at a comparatively narrow
frequency band.

[0013] Therefore, a dual-polarized omni-directional antenna that works at
a comparatively broad frequency band is needed, which may improve the
frequency utilization rate while guaranteeing the frequency band coverage
rate so that the dual-polarized omni-directional antenna may improve the
data transmission rate while occupying a comparatively small space.

SUMMARY OF THE INVENTION

[0014] Embodiments of the present disclosure provides a broadband
dual-polarized omni-directional antenna and a feeding method using the
same in order to solve problems such as a short distance of coverage and
a comparatively low data transmission rate of a traditional
dual-polarized omni-directional antenna.

[0015] A broadband dual-polarized omni-directional antenna is provided.
The broadband dual-polarized omni-directional antenna includes a
vertically polarized antenna 20 and a horizontally polarized antenna 30
each set in co-axial; the horizontally polarized antenna 30 includes an
attaching plate 32 and a folded dipole 31 attached to the attaching plate
32 for receiving and transmitting electromagnetic waves; two arms of the
folded dipole 31 are attached to an upper surface and a lower surface of
the attaching plate 32 respectively, with one arm connecting to an inner
conductor of a first feed line and the other arm connecting to an outer
conductor the first feed line.

[0016] A feeding method using a broadband dual-polarized omni-directional
antenna is also provided. The method includes: using the horizontally
polarized antenna to receive and transmit horizontal polarized waves;
using the vertically polarized antenna to receive and transmit vertical
polarized waves.

[0017] According to the present disclosure, the horizontally polarized
antenna and the vertically polarized antenna are set co-axially; the
vertically polarized antenna is attached to the upper surface and the
lower surface of the attaching plate by the two arms of the folded dipole
and the two arms are connected to the inner conductor and the outer
conductor of the first feed line respectively. Therefore, the broadband
dual-polarized omni-directional antenna according to the present
disclosure may work at a wider frequency band than the traditional
broadband dual-polarized omni-directional antenna and the broadband
dual-polarized omni-directional antenna according to the present
disclosure has a good polarization isolation effect and a uniform
coverage, which may cover 2G, 3G, WLAN (Wireless LAN) and LTE (Long Term
Evolution) systems effectively and may have the performance of MINO
antenna in the LTE and WLAN systems, thus improving the data transmission
rate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to illustrate technical solutions according to the
embodiments of the present disclosure or according to the traditional
technology more clearly, the accompanied drawings needed in describing
the embodiments or the traditional technology will be described briefly.
It is apparent that the accompanied drawings only represent some
embodiments of the present disclosure and those skilled in the art may
obtain other drawings according to the accompanied drawings without
creative labor.

[0019]FIG. 1 is a schematic diagram showing a structure of a
dual-polarized omni-directional antenna according to the prior art;

[0020] FIG. 2(a) is a perspective view of a broadband dual-polarized
omni-directional antenna according to the first embodiment of the present
disclosure;

[0021] FIG. 2(b) is a main view of a broadband dual-polarized
omni-directional antenna according to the first embodiment of the present
disclosure;

[0022] FIG. 2(c) is a top view of a broadband dual-polarized
omni-directional antenna according to the first embodiment of the present
disclosure;

[0023]FIG. 3 is a directional diagram showing a horizontal polarization
in a horizontal plane for a broadband dual-polarized omni-directional
antenna according to the first embodiment of the present disclosure;

[0024] FIG. 4 is a directional diagram showing a vertical polarization
direction in a vertical plane for a broadband dual-polarized
omni-directional antenna according to the first embodiment of the present
disclosure;

[0025] FIG. 5 is a schematic diagram showing an indoor distribution system
shared by LTE, GSM and TD-SCDMA with the broadband dual-polarized
omni-directional antenna according to the present disclosure applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Embodiments of the present disclosure provide a broadband
dual-polarized omni-directional antenna and a feeding method using the
same. The antenna has a dual-polarized structure comprising a
horizontally polarized antenna and a vertically polarized antenna so as
to improve a working efficiency of the antenna. According to the
embodiments, the horizontally polarized antenna may work at a frequency
ranging from 1710 MHz to 2700 MHz. In addition, the vertically polarized
antenna may work at a frequency ranging from 1710 MHz to 2700 MHz and
ranging from 820 MHz to 960 MHz depending on different networks so as to
cover 2G, 3G, WLAN and LTE systems at the same time.

[0027] The technical solutions of the present disclosure will be described
in detail with reference to the drawings and embodiments.

The First Embodiment

[0028] FIG. 2(a), FIG. 2(b) and FIG. 2(c) are a perspective view, a main
view and a top view of a broadband dual-polarized omni-directional
antenna according to the first embodiment of the present disclosure
respectively.

[0029] The broadband dual-polarized omni-directional antenna according to
the first embodiment of the present disclosure includes a substrate 10, a
vertically polarized antenna 20, a horizontally polarized antenna 30 and
a supporting pillar 40. The vertically polarized antenna 20 is disposed
vertically on the substrate 10, the vertically polarized antenna 20 and
the horizontally polarized antenna 30 are set co-axially, and the
supporting pillar 40 is fixed on the substrate 10 and the horizontally
polarized antenna 30 and the supporting pillar 40 is adapted to support
the horizontally polarized antenna 30.

[0030] In addition to supporting the attaching plate 32, the supporting
pillar 40 may help to adjust a standing wave by adjusting a height of the
supporting pillar 40 so as to extend a frequency bandwidth of the
antenna.

[0031] The supporting pillar 40 is made of an insulation material and is
fixed on the attaching plate 32 and the substrate 10 by welding or
riveting.

[0032] The substrate 10 helps to improve a directionality of an antenna
array and to reduce a backward radiation. The substrate 10 may be a
circular plane plate. A material of the substrate 10 may be a conductor
and may be a metal substrate or a substrate with a metal layer such as a
copper or an iron layer overlapped or coated on a top. Preferably, the
substrate 10 may be a copper substrate or an aluminium substrate.

[0033] The horizontally polarized antenna 30 is for receiving and
transmitting horizontally polarized waves and includes an attaching plate
32 and a folded dipole 31 attached to the attaching plate 32 for
receiving and transmitting electromagnetic waves. Two arms of the folded
dipole 31 are attached to an upper surface and a lower surface of the
attaching plate 32 respectively, with one arm connecting to an inner
conductor of a first feed line and the other arm connecting to an outer
conductor the first feed line.

[0034] A number of the folded dipole 31 may be more than one. Preferably,
the horizontally polarized antenna 30 may include an even number of
folded dipoles 31. A plurality of folded dipoles 31 may be distributed on
the attaching plate 32 uniformly and in an axial symmetry. For example,
the horizontally polarized antenna 30 may include 4 folded dipoles 31
with adjacent two folded dipoles forming an angle of 90 degrees so as to
reduce an ovality of the horizontal polarization.

[0035] The folded dipole 31 is formed by two symmetric arms. The two arms
of the folded dipole 31 may be connected in different ways. Specifically,
in the embodiment of the present disclosure, the two arms are connected
through a metallized through hole. The metallized through hole is a hole
through the attaching plate and on an inner surface of the hole, the
metal layer such as the copper layer and the iron layer is disposed by
processes such as overlapping or coating so as to be conductive. The hole
is connected to both the arms on the upper and lower surface of the
attaching plate so that the two arms are connected through the conductive
hole on the attaching plate.

[0036] In order to guarantee a coverage broadness of the antenna, usually
it is required that the ovality (a gain difference between a maximum gain
direction and a minimum gain direction on a directional diagram plane
having an approximately circular shape) of the antenna is less than 2 dB.
In the first embodiment of the present disclosure, in order to reduce the
ovality of the antenna, the arms of the folded dipole 31 may be in a form
of a segment of circular ring or nearly circular ring. In addition, the
arms may have a gap inside and the gap may be in a form of a segment of
circular ring or nearly circular ring.

[0037] The nearly circular ring of the arm or the gap inside the arm of
the folded dipole means that an outer edge of the arm (an outer circle of
the ring) and an inner edge of the arm (an inner circle of the ring) may
be in a form of a nearly arc composed by a plurality of segments.
Specifically, as shown in FIG. 2(c) (the dashed line represents the arms
of the folded dipole on the lower surface of the attaching plate and here
the dashed line is used to only represent one arm of the folded dipole on
the lower surface of the attaching plate and the other three arms are not
shown). The arm of the folded dipole 31 is designed to be a segment of
nearly circular ring and the gap inside the arm is designed to be a
segment of nearly circular ring. FIG. 3 is a directional diagram showing
a horizontal polarization in a horizontal plane for a broadband
dual-polarized omni-directional antenna according to the first embodiment
of the present disclosure. As shown in FIG. 3, the directional diagrams
of the horizontal polarization in the horizontal plane for the antenna
when working at 1880 MHz, 2100 MHz and 2400 MHz are represented by a
dashed line, a dotted line and a solid line respectively. As shown in the
figure, the ovality of the broadband dual-polarized omni-directional
antenna in the horizontal direction is less than 2 dB, which is a general
requirement for ovality for the antennas. FIG. 4 is a directional diagram
showing a vertical polarization direction in a vertical plane for a
broadband dual-polarized omni-directional antenna according to the first
embodiment of the present disclosure. As shown in FIG. 4, the directional
diagrams of the vertical polarization in the vertical plane for the
antenna when working at 870 MHz, 2000 MHz and 2400 MHz are represented by
a dashed line, a dotted line and a solid line respectively. As shown in
the figure, the ovality of the broadband dual-polarized omni-directional
antenna in the vertical direction is less than 2 dB.

[0038] An impedance of the folded dipole changes with a change of an area
of the arm. Therefore, the impedance of the folded dipole may be adjusted
by adjusting the area of the arm. Since the folded dipole has a large
impedance, when the horizontally polarized antenna 30 includes multiple
folded dipoles 31, the impedance of the horizontally polarized antenna
may be matched with a impedance of the feed line by connecting the folded
dipoles 31 in parallel so as to reduce the standing wave ratio (ratio
between the maximum voltage and the minimum voltage) of the broadband
dual-polarized omni-directional antenna provided in the first embodiment
of the present disclosure.

[0039] Specifically, when the folded dipole 31 is connected with the first
feed line, a lead in the arm of the folded dipole 31 is led from an inner
edge of the arm and is connected to the inner conductor or the outer
conductor of the first feed line. Leads of each folded dipole 31
connecting to the inner conductor of the first feed line are connected
together and leads connecting to the outer conductor of the first feed
line are connected together so that the folded dipoles 31 are connected
in parallel. Further, for the convenience of connection, the arms of the
multiple folded dipoles 31 connecting to the inner conductor of the first
feed line may be set on the upper surface (or lower surface) of the
attaching plate 32 and the leads connecting to the inner conductor of the
first feed line may be connected together; the arms of the multiple
folded dipoles 31 connecting to the outer conductor of the first feed
line may be set on the lower surface (or upper surface) of the attaching
plate and the leads connecting to the outer conductor of the first feed
line may be connected together. Thus the multiple folded dipoles 31 are
connected in parallel and the number of connecting lines may be reduced.

[0040] A shape of the attaching plate 32 includes but is not limited to
circular, rectangular or other polygons. Preferably, the attaching plate
32 is designed to be circular. The two arms of the folded dipole 31 may
be but not limited to be welded to the surface of the attaching plate 32.
An outer edge of the arm of the folded dipole 31 is adjacent to an outer
edge of the attaching plate 32 and an inner edge of the arm is adjacent
to a center of the attaching plate 32.

[0041] The vertically polarized antenna 20 is used for receiving and
transmitting vertically polarized waves. A material of the vertically
polarized antenna 20 may be of a metal structure or structures with a
copper or an iron layer overlapped or coated on a surface. Preferably,
the vertically polarized antenna 20 may be a copper structure or an
aluminium structure. The vertically polarized antenna 20 may have
different structures. Specifically, as shown in FIG. 2(a) (the dashed
line represents the arm of the folded dipole on the lower surface of the
attaching plate and here the dashed line is used to only represent one
arm of the folded dipole on the lower surface of the attaching plate and
the other three arms are not shown), the vertically polarized antenna 20
includes an antenna component 22 in a form of spherical segment and an
antenna component 21 in a form of cone extending from a lower end of the
antenna component 22 in the form of spherical segment, and the antenna
component 21 in the form of cone is connected with a second feed line.
Specifically, feed points on the antenna component 21 in a form of cone
may be connected with the second feed line through the round hole on the
substrate 10 and the antenna component 21 in a form of cone is integrated
with the substrate 10 through the hole and the second feed line that
passes through the hole.

[0042] As shown in FIG. 2(b), the first feed line may come in through a
side surface of the antenna component 22 in the form of spherical segment
and come out through a top end of the antenna component 22 in the form of
spherical segment so as to connect with lead of the arm of the folded
dipole through an opening on a vertically polarized guide sheet 50.
Preferably, as shown in FIG. 2(b), one supporting component may be added
to support the vertically polarized antenna 20.

[0043] In order to reduce interference between the horizontally polarized
antenna 30 and the vertically polarized antenna 20 and to improve a
polarization isolation of the broadband dual-polarized omni-directional
antenna provided in the first embodiment of the present disclosure, the
horizontally polarized antenna 30 and the vertically polarized antenna 20
may be set co-axially. In order to reduce a coupling between the
horizontally polarized antenna 30 and the vertically polarized antenna
20, a distance between the lower surface of the attaching plate 32 of the
horizontally polarized antenna 30 and the vertically polarized antenna 20
may be set in a range from 8 mm to 15 mm. For example, when the
vertically polarized antenna includes the antenna component 22 in a form
of spherical segment and the antenna component 21 in a form of cone
extending from a lower end of the antenna component 22 in the form of
spherical segment, the vertical distance between the lower surface of the
attaching plate 32 of the horizontally polarized antenna 30 and a top end
of the antenna component 22 in a form of spherical segment of the
vertically polarized antenna 20 ranges from 8 mm to 15 mm.

[0044] In order to broaden the bandwidth of the vertically polarized
antenna 20 and to further reduce the coupling between the horizontally
polarized antenna 30 and the vertically polarized antenna 20, as shown in
FIG. 2(b), the first embodiment of the present disclosure provides a
broadband dual-polarized omni-directional antenna which further includes
a vertically polarized guide sheet 50 and a connecting component 60. The
connecting component 60 is made from a non-conductive material and is
fixed on the attaching plate 32 and the coupling component 50 by welding
or riveting so that the vertically polarized guide sheet 50 is located
between the horizontally polarized antenna and the vertically polarized
antenna. That is to say, the upper surface of the vertically polarized
guide sheet 50 is not in contact with the lower surface of the attaching
plate 32 of the horizontally polarized antenna 30 and the lower surface
of the vertically polarized guide sheet 50 is not in contact with the
vertically polarized antenna either. The vertically polarized guide sheet
50 may be but not limited to in a form of circle. Specifically, the
vertically polarized guide sheet may be designed to be circle.

[0045] By setting the vertically polarized guide sheet 50 between the
vertically polarized antenna 20 and the horizontally polarized antenna
30, the bandwidth of the vertically polarized antenna 20 may be broadened
and the coupling between the vertically polarized antenna 20 and the
horizontally polarized antenna 30 may be reduced.

The Second Embodiment

[0046] The second embodiment of the present disclosure provides a feeding
method using the broadband dual-polarized omni-directional antenna
according to the first embodiment. According to the method, the
horizontally polarized antenna is used to receive horizontal polarized
waves and the vertically polarized antenna is used to receive vertical
polarized waves. The received radio waves are converted to a high
frequency current and then output through the first feed line and the
second feed line. According to the method, the received high frequency
current is converted into the radio waves and then output through the
first feed line and the second feed line to the antenna; the horizontally
polarized antenna is used to transmit the horizontal polarized waves and
the vertically polarized antenna is used to transmit the vertical
polarized waves.

[0047] In addition to the advantages of high frequency band coverage and
high data transmission rate, the broadband dual-polarized
omni-directional antenna provided in the embodiment of the present
disclosure has the advantage of reducing the ovality of the broadband
dual-polarized omni-directional antenna by mounting the multiple folded
dipoles on the attaching plate in symmetry and by designing the arm of
the folded dipoles to a segment of circular ring or by designing a gap in
a form of a segment of circular ring in the arm. By connecting the
multiple folded dipoles in parallel, the standing wave of the broadband
dual-polarized omni-directional antenna can be reduced. By setting the
arms connecting the inner conductor of the feed line on the same surface
of the attaching plate, the number of the connecting lines can be
reduced. According to the embodiment of the present disclosure, by
setting the vertically polarized guide sheet 50 between the vertically
polarized antenna 20 and the horizontally polarized antenna 30, the
bandwidth of the vertically polarized antenna 20 can be broadened and the
coupling between the vertically polarized antenna 20 and the horizontally
polarized antenna 30 can be reduced so that the performance of the
broadband dual-polarized omni-directional antenna can be optimized.

[0048] In addition to working as the MIMO antenna in the TD-LTE and WLAN
systems, the dual-polarized omni-directional antenna provided in the
embodiment of the present disclosure may cover frequency bands of the
GSM, CDMA, WCDMA, CDMA2000, TD-SCDMA, TD-LTE and WLAN by using the
vertically polarized dipole as the traditional mono-polarized (ceiling)
antenna, which may be independently used in the GSM and CDMA indoor
coverage systems. In the 3G systems such as the WCDMA, CDMA2000 and
TD-SCDMA systems, the vertically polarized dipole and the horizontally
polarized dipole of the dual-polarized omni-directional antenna may be
combined to form a dual channel antenna for receiving and transmitting
the radio waves. That is to say, by using the technical solutions
provided in the embodiments of the present disclosure, the uplink and
downlink signal transmission quality may be improved for different kinds
of networks such as GSM, CDMA, WCDMA, TD-SCDMA, LTE and WLAN. In the LTE
and WLAN in compliance with 802.11n, the MIMO antenna technology may be
used directly by using the multiple antennas and multiple channels
provided in the embodiments of the present disclosure, the uplink and
downlink coverage and the transmission rate of the indoor distribution
system may be improved. Therefore, the embodiments of the present
disclosure may be used in the 2G, 3G and WLAN systems at the same time
and may be smoothly used in the LTE system, which has the function of
covering all the current indoor distribution systems.

[0049] For example, as shown in FIG. 5, the broadband dual-polarized
omni-directional antenna according to the embodiment of the present
disclosure may be applied in an indoor distribution system shared by LTE,
GSM and TD-SCDMA. As shown in FIG. 5, the shared indoor distribution
system is distributed in area A, area B and area C where one broadband
dual-polarized omni-directional antenna according to the embodiment of
the present disclosure may be arranged in each radiating node, in which
the vertically polarized antenna may cover the frequency band of 820
MHz˜960 MHz and 1710 MHz˜2700 MHz while the horizontally
polarized antenna may cover the frequency band of 1710 MHz˜2700
MHz.

[0050] Next, area A will be taken as an example to illustrate the
procedure of using the broadband dual-polarized omni-directional antenna
for area A according to the embodiment of the present disclosure.

[0051] When a TD-SCDMA terminal needs to transmit an uplink signal, for
example when the 1880˜1920 MHz and 2010˜2025 MHz frequency
bands are used, an antenna covering both 1880˜1920 MHz and
2010˜2025 MHz frequency bands should be selected from the indoor
dual-polarized omni-directional antenna.

[0052] It is assumed that in area A in each dual-polarized
omni-directional antenna radiation node (node 1, node 2 and node 3), both
the vertically polarized antenna and the horizontally polarized antenna
may cover the 1880˜1920 MHz and 2010˜2025 MHz frequency
bands, i.e. in each node within area A there are two polarized antennas
covering the 1880˜1920 MHz and 2010˜2025 MHz frequency bands.
Therefore, two differently polarized antennas (i.e. vertically polarized
antenna and horizontally polarized antenna) covering both the
1880˜1920 MHz and 2010˜2025 MHz frequency bands may be
selected from the radiation node 1.

[0053] When the two antennas for receiving the uplink signals transmitted
from the TD-SCDMA terminal are determined, they begin to receive the
uplink signals transmitted from the TD-SCDMA terminal respectively and
combine the two path signals received in diversity into one path uplink
signal and the procedure for combining the signals is described below.

[0054] In radiation node 1, the vertically polarized antenna and the
horizontally polarized antenna receive two path uplink signals in
diversity and transmit the signals through their own channels
respectively.

[0055] The uplink signals transmitted in the channel corresponding to the
horizontally polarized antenna and the uplink signals transmitted in the
channel corresponding to the vertically polarized antenna are transmitted
to an uplink signal destination TD-SCDMA network element (such as the
TD-SCDMA base station) of the TD-SCDMA terminal together through the RRU
and BBU of the dual channels and are combined into one path uplink signal
at the base station. The destination TD-SCDMA network element combines
the received uplink signals into one path signal and realizes receiving
the uplink signals transmitted by the TD-SCDMA terminal together by using
the dual-polarized omni-directional antenna that may be integrated with
one vertically polarized antenna and one horizontally polarized antenna.

[0056] When an LTE terminal needs to transmit an uplink signal, for
example when the 2300 MHz˜2400 MHz frequency band is used, one
vertically polarized antenna and one horizontally polarized antenna both
covering 2300 MHz˜2400 MHz frequency band may be selected in
radiation node 1 with in area A to utilize the MIMO antenna technology to
improve the network coverage and the data transmission rate and the
detailed method will not be illustrated in detail here.

[0057] Apparently, those skilled in the art may make any changes,
alternatives and modifications to the present disclosure without
departing from spirit and principles of the disclosure. Thus when the
changes, alternatives, and modifications belong to the scope of protected
by the claims and the equivalent, the present disclosure intends to
include the changes, alternatives and modifications.

Patent applications by Feng Gao, Beijing CN

Patent applications by Jiwei He, Beijing CN

Patent applications by Peng Gao, Beijing CN

Patent applications by Wentao Zhu, Beijing CN

Patent applications by Xu Liu, Beijing CN

Patent applications in class Having a plurality of contiguous regions served by respective fixed stations

Patent applications in all subclasses Having a plurality of contiguous regions served by respective fixed stations